Biomedical subjects

Hayao Nakanishi

Publications and source records attributed to Hayao Nakanishi.

At least 19 recordsLinked to original sources

PubMed2006

2-Deoxy-L-ribose inhibits the invasion of thymidine phosphorylase-overexpressing tumors by suppressing matrix metalloproteinase-9.

Thymidine phosphorylase (TP), an enzyme involved in pyrimidine metabolism, is identical with an angiogenic factor, platelet-derived endothelial cell growth factor. 2-Deoxy-D-ribose (D-dRib), the degradation product of thymidine generated by TP activity, has been suggested to be a downstream mediator of TP function. 2-Deoxy-L-ribose (L-dRib), a stereoisomer of D-dRib, inhibited the promotion of angiogenesis, tumor growth and metastasis by TP. In our study, we have shown that nude mice inoculated with TP-overexpressing KB/TP cells had shorter survival times than those injected with control KB/CV cells. KB/TP tumors were also more highly invasive than KB/CV tumors in mice. The expression levels of matrix metalloproteinase (MMP)-9 in KB/TP tumors were significantly higher than those in KB/CV tumors. L-dRib and a TP inhibitior, TPI, extended the survival period of KB/TP tumor-bearing mice. L-dRib also reduced MMP-9 mRNA levels in KB/TP tumors. Furthermore, L-dRib suppressed the mRNA level of MMP-9 in cultured KB/TP cells, and the invasive activity of the cells. L-dRib may be useful for the suppression of invasion of TP-expressing tumor cells.

Animals↗

PubMed2006

A polymorphism of C-to-T substitution at -31 IL1B is associated with the risk of advanced gastric adenocarcinoma in a Japanese population.

Proinflammatory cytokine gene polymorphisms have been demonstrated to associate with gastric cancer risk, of which IL1B-31T/C and -511C/T changes have been well investigated due to the possibility that they may alter the IL1B transcription. The signal transduction target upon interleukin 1 beta (IL1beta) stimulation, the nuclear factor of kappa B (NFkappaB) activation, supports cancer development, signal transduction in which is mediated by FS-7 cell-associated cell surface antigen (FAS) signaling. Based on recent papers describing the prognostic roles of the polymorphisms and the NFkappaB functions on cancer development, we sought to determine if Japanese gastric cancer patients were affected by the IL1B -31/-511 and FAS-670 polymorphisms. A case-control study was conducted on incident gastric adenocarcinoma patients (n=271) and age-gender frequency-matched control subjects (n=271). We observed strong linkage disequilibrium between the T allele at -511 and the C allele at -31 and between the C allele at -511 and the T allele at -31 in IL1B in both the cases and controls (R (2)=0.94). Neither IL1B-31, -511 nor FAS-670 polymorphisms showed significantly different risks of gastric adenocarcinoma. Though FAS-670 polymorphisms did not show any significant difference, the proportion of subjects with IL1B-31TT (or IL1B-511CC) increased according to stage (trend P=0.019). In particular, subjects with stage IV had a two times higher probability of having either IL1B-31TT (or IL1B-511CC) genotype compared with stage I subjects. These observations suggest that IL1B-31TT and IL1B-511CC are associated with disease progression.

Adenocarcinoma↗

PubMed2006

A carbohydrate recognition-based drug delivery and controlled release system using intraperitoneal macrophages as a cellular vehicle.

The lymphoid tissue in the omentum, at the so-called milky spots, is known as an initial place for disseminated cancer cells to develop into solid tumors. In the present study, i.p. macrophages significantly took up oligomannose-coated liposomes (OMLs) that were injected into the peritoneal cavity, and then gradually accumulated in the omentum and the other lymphoid tissues within 24 hours of i.p. injection of OMLs. When 5-fluorouracil (5-FU) was encapsulated in the OMLs, >60% of administered 5-FU accumulated in the omentum. Treatment of macrophages at 39 degrees C for 30 minutes led to the release of 5-FU from the macrophages, suggesting that controlled release from macrophages could be achieved by mild hyperthermia. We encased magnetic nanoparticles, which are known to convert electromagnetic energy to heat in the OMLs to achieve in vivo hyperthermia at the site. Using this system in a mouse i.p. metastasis model, we successfully controlled tumor development by coadministration of OML-encased 5-FU and OML-encased magnetic nanoparticles, followed by treatment with an alternating magnetic field. No apparent reduction was seen in tumor growth with the administration of OML-encased magnetic nanoparticles or OML-encased 5-FU alone. Thus, we have established the use of i.p. macrophages as a novel drug delivery system for the control of cancer metastatic to milky spots.

Animals↗

PubMed2006

Apical Golgi localization of N,N'-diacetyllactosediamine synthase, beta4GalNAc-T3, is responsible for LacdiNAc expression on gastric mucosa.

beta1,4-N-acetylgalactosaminyltransferase III (beta4GalNAc-T3), which was recently cloned and identified, exhibits GalNAc transferase activity toward a GlcNAcbeta residue with beta1,4-linkage, forming the N,N'-diacetyllactosediamine, GalNAcbeta1,4GlcNAc (LacdiNAc or LDN). Though LacdiNAc has not been found in the gastric mucosa, a large amount of transcript was detected in our previous study. To increase our knowledge of beta4GalNAc-T3 expression and its product LacdiNAc, we examined the exact localization of beta4GalNAc-T3 in human gastric mucosa using a newly developed antibody, monoclonal antibody (mAb) K1356. This antibody specifically detected the enzyme that transfected the beta4GalNAc-T3 gene into MKN45 cells, and the terminal betaGalNAc epitope yielded on the cell surface was recognized by a lectin, Wisteria floribunda agglutinin (WFA). beta4GalNAc-T3 was localized in the supra-nuclear region of surface mucous cells in gastric mucosa, and WFA positively stained the mucins secreted by the cells. In contrast, in the cells of the glandular compartment in the fundic glands and a few cells in the pyloric glands, beta4GalNAc-T3 was observed in the basolateral position of the nucleus, where no WFA reactivity was detected. The anti-Tn (GalNAcalpha-O-Ser/Thr) antibody staining did not overlap with the WFA staining. By measuring the binding activity of WFA using automated frontal affinity chromatography (FAC), we found WFA to bind most strongly LacdiNAc among the sugar chains examined. Neither beta4GalNAc-T3 nor WFA-positive staining was detected in intestinal metaplastic cells. These results suggest that the supra-nuclear expression of beta4GalNAc-T3 is essential for the formation of LacdiNAc on the surface mucous cells and that LacdiNAc and beta4GalNAc-T3 are novel differentiation markers of surface mucous cells in the gastric mucosa.

Antigens, Differentiation↗

PubMed2006

Immunocytochemical detection using CDX2: An aid for discerning tumor involvement in ascites cytology.

BACKGROUND: Although ascites cytology is important for therapeutic strategies, it is difficult to distinguish cancer infiltration from reactive mesothelial proliferation in some patients. In this study, the authors applied CDX2 immunocytochemistry to improve diagnostic accuracy. METHODS: The authors examined the distribution of CDX2 expression in carcinoma specimens using paraffin-embedded tissues from various organs from 549 cancer patients. CDX2 immunostaining was applied to the 116 ascites specimens. RESULTS: CDX2 expression was detected in a restricted range of cancers, with the vast majority of them originating from the gastrointestinal tract and pancreas. When applied to ascites specimens, no positive reactions were detected in any of the 81 cytology-negative and molecular genetic analysis-negative specimens. By contrast, 28 of 35 specimens diagnosed as suspicious for malignancy or malignancy showed a positive reaction. Furthermore, the authors found that a nuclear-positive reaction was easily evaluated, even with a high level of background staining, and single cancer cells in 10(6) normal cells could be detected. CONCLUSION: Results suggest that CDX2 is a specific and sensitive marker to detect gastrointestinal and pancreatic malignancies in ascites cytology.

Adenocarcinoma↗

PubMed2006

Biological significance of isolated tumor cells and micrometastasis in lymph nodes evaluated using a green fluorescent protein-tagged human gastric cancer cell line.

PURPOSE: The biological significance of isolated tumor cells and micrometastasis in lymph node defined by the International Union against Cancer remains essentially unknown because of the lack of appropriate animal models. In the present study, we developed a lymph node micrometastasis model featuring a human gastric cancer cell line tagged with green fluorescent protein gene (GCIY-EGFP), which allows visualization of even isolated tumor cells in the development of metastasis without histologic procedure. Using this model, we investigated the effect of surgery and chemotherapy on the growth of early-phase metastasis formation in the lymph nodes. EXPERIMENTAL DESIGN: The time course of spontaneous inguinal lymph node metastasis after s.c. inoculation of GCIY-EGFP cells into nude mice was examined with fluorescence dissecting microscopy. Then, the effects of surgical removal of the primary tumor with or without anti-asialo GM1 treatment or postoperative chemotherapy on the growth of isolated tumor cells and micrometastasis in the lymph nodes were examined. RESULTS: GCIY-EGFP cells were found to metastasize spontaneously to the inguinal lymph nodes to form isolated tumor cells, micrometastasis, and, finally, develop macroscopic metastasis at 1 to 2, 3 to 5, and 5 weeks postinjection, respectively. When the primary tumors were removed within 2 weeks of inoculation, isolated tumor cells, but not micrometastasis, in the lymph nodes regressed by 4 weeks after surgery in all the mice examined (five of five). This spontaneous regression of isolated tumor cells was completely reversed by anti-asialo GM1 treatment, which could deplete natural killer cells effectively in nude mice. Chemotherapy following resection of the primary tumor at an early stage partially eliminated the remaining micrometastasis in the lymph nodes. CONCLUSIONS: These results suggest that isolated tumor cells in the regional lymph nodes regressed by removal of the primary tumor mainly via natural killer cell-mediated antitumor activity and that micrometastasis in the lymph nodes could be effectively eliminated by the postoperative chemotherapy.

Animals↗

PubMed2005

Prognostic significance of intraperitoneal cancer cells in gastric carcinoma: analysis of real time reverse transcriptase-polymerase chain reaction after 5 years of followup.

BACKGROUND: The presence of gastric cancer cells in the peritoneal cavity detected by cytologic examination is an important prognostic factor. A reverse transcriptase-polymerase chain reaction (RT-PCR) technique amplifying carcinoembryonic antigen mRNA was recently introduced to detect these cells more sensitively. STUDY DESIGN: Five-year followup was completed for 284 gastric carcinoma patients who underwent CEA RT-PCR testing. Analyses to assess the accuracy and prognostic value of this procedure were performed, along with univariate and multivariable analyses to evaluate RT-PCR as a technique with peritoneal carcinomatosis and cancer death as the outcomes variables. RESULTS: CEA mRNA levels exceeded the cutoff value defining a positive result in 9.5%, 29%, 66%, and 81% of patients with pT1, pT2, pT3, and pT4 stage disease, respectively. Sensitivity, specificity, positive predictive value, and negative predictive value for peritoneal carcinomatosis within 5 years of surgery were 88.5%, 81.6%, 64.5%, and 94.9%, respectively. Multivariable analysis revealed that a positive CEA mRNA result was an independent risk factor for cancer death (hazard ratio 2.82, 95% CI 1.17 -3.07) among 274 patients (10 patients with no record of nodal status were excluded from the analysis) and for peritoneal carcinomatosis (hazard ratio 1.57, 95% CI 1.07-2.29) among 242 patients who had no peritoneal deposits at operation. CONCLUSIONS: CEA RT-PCR is useful as a prognostic marker for increased risk of cancer death and peritoneal carcinomatosis, and might be useful in the clinical setting for selecting patients for various adjuvant treatments.

Aged↗

PubMed2005

Prognostic significance of intraperitoneal cancer cells in gastric carcinoma: detection of cytokeratin 20 mRNA in peritoneal washes, in addition to detection of carcinoembryonic antigen.

BACKGROUND: In patients with gastric cancer, the presence of gastric cancer cells in the peritoneal cavity detected by cytologic examination, is a significant prognostic factor. A more sensitive, reverse transcriptase-polymerase chain reaction (RT-PCR) technique, amplifying carcinoembryonic antigen (CEA), was introduced as a new detection system, but produced some false-positive results. A search for other molecular markers is ongoing. METHODS: Peritoneal washes were obtained from 195 patients with gastric carcinoma during surgery. Cytokeratin 20 (CK20) mRNA levels were quantified, in addition to those of CEA, using the LightCycler, and the feasibility of CK20 as a target was evaluated. RESULTS: CK20 was limited, in terms of sensitivity, for detecting disseminated cancer cells (sensitivity, 63%; specificity, 91%; positive predictive value, 70%; and negative predictive value, 88%). Multimarker analysis was performed, in which samples positive for either CK20 or CEA mRNA were considered to be positive for cancer cells. Multivariate analysis identified the multimarker analysis as a significant independent prognostic determinant. CONCLUSION: CK20 RT-PCR produced information that could add a significant impact to the knowledge obtained by CEA RT-PCR, although detection by CK20 alone was not sufficiently sensitive to replace CEA in the detection system.

Biomarkers, Tumor↗

PubMed2005

Establishment and characterization of three novel human gastric cancer cell lines with differentiated intestinal phenotype derived from liver metastasis.

Gastric cancers with liver metastasis are fatal diseases with rapid progression and poor patient outcome. To date, however, the molecular basis of their growth and metastasis remains essentially unknown, largely because of the presence of few available gastric cancer cell lines established from liver metastasis. In the present study, we developed two novel cultured cell lines (designated GLM-1 and GLM-2) and one transplantable line in nude mice (designated GLM-3) derived from liver metastasis of gastric cancer patients. These GLM cell lines share unique biological features such as differentiation, growth and metastasis. They form moderately differentiated tumors with CD10 positive and MUC2 negative intestinal absorptive phenotype when injected into nude mice. Their growth is stimulated by EGF and TGF-alpha in vitro like other gastric cancer cell lines. However, GLM cells differ from conventional gastric cancer cell lines in their high apoptotic rate, even in the absence of apoptosis inducing stimuli as revealed by Caspase3/7 assay and the TUNEL method. This apoptosis is further enhanced by phosphatidylinositol 3-kinase (PI3K) inhibitor (LY294002), but not by MEK1/2 inhibitor (U0126), indicating the strong dependency of their survival on PI3K/Akt pathway rather than MAPK pathway, the major downstream signaling pathways of EGFR. GLM-1 cells can metastasize to the liver after intrasplenic injection, and GLM-3 cells have spontaneous lung metastatic potential after subcutaneous transplantation, respectively. These results indicate that the GLM series are the first cell lines reflecting the intestinal-type differentiated adenocarcinoma, a major subtype of gastric cancer with liver metastasis. Therefore, they would be excellent models for understanding the mechanism of metastatic growth and the development of a new molecular targeting therapy for gastric cancer with liver metastasis.

Adenocarcinoma↗

PubMed2005

Helicobacter pylori-dependent NF-kappa B activation in newly established Mongolian gerbil gastric cancer cell lines.

Mongolian gerbils are an ideal animal model to explore the role of H. pylori on cancer development. However, there have been no established adenocarcinoma cell lines from this model animal. In the present study, we have established cancer cell lines from a primary gastric cancer tissue of a Mongolian gerbil. The derived cells could be stably attached with H. pylori, revealed under a scanning electron microscope, and easily transplanted to the nude mice. Rapid phosphorylation of IkappaB, Erk1/2, and AKT of these cells was observed by Interleukin-1 beta stimulation, and luciferase reporter gene assay on transcriptional activation of Nuclear Factor kappa B after challenging with either H. pylori NCTC11637 or its isogenic cagE-knockout mutant, H. pylori revealed the cagE-dependent NF-kappaB transcriptional activation. The newly established cancer cell lines from the in vivo gastric carcinogenesis model animal, the Mongolian gerbil, can be used to develop effective therapeutic strategies against gastric cancer, especially in exploring the effect of H. pylori, and thus might greatly contribute to gastric cancer prevention and treatment in humans.

Animals↗

PubMed2005

Establishment and characterization of a human colonic mucinous carcinoma cell line with predominant goblet-cell differentiation from liver metastasis.

Many human colorectal adenocarcinoma cell lines have been developed. However, differentiated type colorectal cancer cell lines, particularly, the goblet-cell differentiated type, are scarce. In the present study a novel colorectal adenocarcinoma cell line (designated as COLM-6) with predominant goblet-cell differentiation was established from the rectal mucinous adenocarcinoma of a Japanese woman. COLM-6 cells grow in a typical epithelial monolayer in culture. They expressed epidermal growth factor (EGF) receptor and HER2 on their surface and accordingly, their growth was significantly stimulated by EGF, transforming growth factor (TGF)-alpha and heregulin. COLM-6 cells form tumor with typical mucinous adenocarcinomatous appearance in nude mice. Immunohistochemical analysis of these subcutaneous tumors demonstrated that COLM-6 cells strongly express MUC2 as a goblet-cell marker and Cdx2 in the nucleus. Some weakly express villin and carbonic anhydrase 1 as a columnar absorptive-cell marker as well. They were also positive for adenomatous polyposis coli (APC) cytoplasmically and expressed beta-catenin in their cytoplasm and cell membrane without nuclear accumulation. These results indicate that COLM-6 cell line has unique characteristics and may provide a useful tool to study the mechanism of growth and differentiation of colonic epithelium as well as the biological behavior of colorectal mucinous adenocarcinoma.

Adenocarcinoma, Mucinous↗

PubMed2005

Mixed gastric- and intestinal-type metaplasia is formed by cells with dual intestinal and gastric differentiation.

We have proposed to divide intestinal metaplasia (IM) into two categories, i.e., a mixed gastric and intestinal (GI) type, and a solely intestinal (I) type, based on the residual gastric phenotype cells. The GI-mixed-type IM can be identified by the presence of both cells with either gastric or intestinal phenotypes in a single gland. This study is conducted to elucidate whether cells in the GI-mixed-type IM glands can simultaneously present both gastric and intestinal phenotypes. MUC5AC, MUC2, CD10 and villin expressions were investigated in 20 samples from five gastric cancer cases, directly using either AlexaFluor 488- or 568-labeled specific monoclonal antibodies and observed by fluorescent microscopy and confocal laser-scanning microscopy. GI-mixed IM glands comprise a population expressing MUC5AC and MUC2, MUC5AC and villin, and MUC5AC and CD10. MUC2 and villin expressions were reciprocally increased with decreasing MUC5AC expression, while CD10 expression was limited to cells with only a residual MUC5AC expression or no expression. These results suggest that a heterogeneous cell population with both gastric and intestinal phenotypes would develop into a single intestinal phenotype, as reflected in the progression of intestinal metaplasia from GI-mixed-type- to I-type IM-type glands.

Animals↗

PubMed2005

Evaluation of chemosensitivity of micrometastases with green fluorescent protein gene-tagged tumor models in mice.

The chemosensitivity of micrometastasis is an important factor in therapeutic approaches to micrometastasis. The protocol in this chapter presents procedures capable of examining the drug sensitivity of micrometastases to anticancer agents, especially those in the peritoneal cavity, lymph nodes, and the lung in mice. The protocol consists of green fluorescent protein (GFP) gene-tagged metastasis models in mice and unique detection devices for GFP. The latter include a small, convenient stereo fluorescent microscope for internal visualization of micrometastases at the cellular level with magnification and a handy GFP detection device for external, noninvasive monitoring of therapeutic effect of a drug without magnification. Mice are injected with GFP-tagged tumor cells and divided into an early and a late administration group according to the timing of drug administration. Early administration starts from 1-2 d postinjection for peritoneal and lung metastases and 2-3 wk after subcutaneous injection for lymph node metastasis, when the micrometastasis macroscopically remains invisible--less than 0.5 mm in maximum diameter--as confirmed by the detection device. The results thus obtained indicate that micrometastases are more sensitive to anticancer agents than advanced metastases. This system using GFP-tagged tumor models is an indispensable tool for micrometastasis research.

Animals↗

PubMed2005

Efficacy of intraperitoneal chemotherapy with paclitaxel targeting peritoneal micrometastasis as revealed by GFP-tagged human gastric cancer cell lines in nude mice.

To explore the effect of chemotherapy against peritoneal micrometastases, we used in vivo models of peritoneal micrometastasis featuring three human gastric cancer cell lines tagged with the green fluorescence protein gene. With a highly metastatic cell line, GCIY-EGFP, the survival rate of mice treated with weekly intraperitoneal paclitaxel starting one day following inoculation was significantly higher than those of control mice or mice given the same treatment starting on day eight. Intravenous paclitaxel exhibited no significant survival benefit regardless of the treatment schedule. Pharmacokinetic analysis revealed that the concentration of paclitaxel in the metastatic nodules treated with intraperitoneal administration was 2-3-fold higher than those treated with intravenous paclitaxel, provided the treatment was given on day one. Even greater responses were observed with less aggressive MKN28-EGFP and MKN45-EGFP cell lines, whose peritoneal metastases resolved completely due to early intraperitoneal treatment in 13 of the 14 mice tested. These results indicate that intraperitoneal paclitaxel is effective against peritoneal metastasis in early phase.

Animals↗

PubMed2005

The effect of storage on the survival of cancer cells in blood and efficient elimination of contaminating cancer cells by a leukocyte depletion filter.

Preoperative autologous blood pooling has been employed in patients with malignant tumor. However, it has not been reported how the survival period of tumor cells contaminating the preoperative pooled blood changes corresponding to the storage period. Intraoperative blood salvage (IBS) is used together with preoperative blood pooling. However, IBS in oncologic surgery is generally regarded as a contraindication. In the current study, using cytokeratin 19 (CK-19) mRNA reverse transcription polymerase chain reaction method, we examined the survival period of cultured cancer cells in the pooled blood and the efficacy of irradiation and leukocyte depletion filter in eliminating cancer cells in the blood. Expression of CK-19 mRNA was observed in the pooled blood stored for 21 days. The number of cancer cells decreased to about 1/10 in the blood stored for 14 days. We irradiated blood with cancer cells with doses of 25 Gy or 100 Gy. No change was observed in the amplified CK-19 signal strength immediately after and 1 day after irradiation at 100 Gy. After filtration of blood with cancer cells through the leukocyte depletion filter, no CK-19 mRNA was detected. Blood filtration with the leukocyte depletion filter was effective in eliminating cancer cells in the blood.

Blood Preservation↗

PubMed2004

Inhibition of experimental lung metastases of Lewis lung carcinoma cells by chemically modified heparin with reduced anticoagulant activity.

Heparin, a widely used anticoagulant, is known to have anti-metastatic activity, although the mechanism is not fully understood. In the present study, we investigated the mechanism of this anti-metastatic activity using periodate-oxidized and borohydride-reduced heparin with low anticoagulant activity (LAC heparin). The anticoagulant activity of LAC heparin is markedly reduced to almost the control level in terms of prothrombin time in vitro, and no hemorrhagic complication was observed with injection of LAC heparin into mice in vivo. LAC heparin injected intravenously with Lewis lung carcinoma cells or 10 min before tumor cell injection significantly inhibited, to the same extent as intact heparin and in a dose- and time-dependent manner, the lung colonization that develops after intravenous injection (i.v.) of tumor cells. Flow cytometric analysis revealed that Lewis lung carcinoma cells strongly express heparan sulfate on their surface. Both the LAC heparin and intact heparin inhibited the adhesion and invasion of tumor cells to Matrigel-coated dishes in vitro without significant effect on the tumor cell growth. LAC heparin also significantly diminished tumor cell retention in the lung after i.v. of LacZ gene-tagged Lewis lung carcinoma cells. These results suggest that LAC heparin may prevent tumor cells from attachment to the subendothelial matrix of lung capillaries by competitively inhibiting cell surface heparan sulfate functions and suppress lung colonization.

Animals↗

PubMed2004

TNF-alpha promotes progression of peritoneal metastasis as demonstrated using a green fluorescence protein (GFP)-tagged human gastric cancer cell line.

The mechanisms underlying progression of peritoneal metastasis by gastric cancer after micrometastasis formation remain unclear. In the present study, we investigated metastasis to the abdominal wall peritoneum, one of the major features of peritoneal spread, using a human gastric cancer cell line (GCIY-EGFP) tagged with the green fluorescence protein gene (GFP). This model allows sensitive, specific and sequential observation of metastasis development from the initial deposits to peritoneal carcinomatosis at the end stage. In the initial phase, GCIY-EGFP cells could form micrometastasis selectively on the omentum and mesenterium in a milky spot-dependent manner, but not on abdominal wall peritoneum lacking milky spots until the late stages. In vitro analysis using primary mesothelial cells revealed addition of TNF-alpha to decrease their stress fibers, leading to morphological change followed by exposure of the submesothelial extracellular matrix (ECM) in intercellular gaps. Such TNF-alpha pretreatment was found to enhance attachment of tumor cells to the mesothelial monolayer. When tumor cells were injected into the peritoneal cavity of TNF-alpha pretreated mice, they could metastasize to the abdominal wall peritoneum from the very early stages, resulting in accelerated accumulation of ascites than in TNF-alpha non-pretreatment controls. RT-PCR analysis revealed that tumor cells express cytokines and chemokines, including TNF-alpha. Furthermore, TNF-alpha treatment results in up-regulation of expression of monocyte chemoattractant protein-1 (MCP-1) and IL-8 by mesothelial cells and of TNF-alpha itself by inflammatory leukocytes in the peritoneal cavity. These results suggest that metastasis to the abdominal wall peritoneum occurs as a second step from the first omental metastasis in a milky spot-independent manner and that TNF-alpha derived from tumor cells, mesothelial cells and inflammatory leukocytes in the peritoneal cavity may be involved in the progression of peritoneal metastasis.

Adenocarcinoma↗

PubMed2004

Detection of disseminated cancer cells in linitis plastica-type gastric carcinoma.

BACKGROUND: Dissemination of cancer cells in the abdominal cavity may lead to peritoneal carcinomatosis, a common event in the linitis plastica type of gastric carcinoma. Reverse transcriptase polymerase chain reaction (RT-PCR) is a sensitive technique for detecting these cells. METHODS: Peritoneal washings were obtained during laparotomy from 47 consecutive linitis plastica patients who preoperatively were considered candidates for curative resection. Together with conventional cytological examination using Papanicolaou staining, real-time RT-PCR was performed to quantitate prospectively carcinoembryonic antigen (CEA) mRNA in these washings. Samples above a cutoff value for CEA mRNA were considered positive for molecular detection of disseminated cancer cells. RESULTS: Conventional cytological examination was positive in 43% (20/47). Positivity of CEA mRNA was much higher at 83% (39/47) and peritoneal carcinomatosis actually was observed in 77% (36/47), either at laparotomy or during postoperative follow-up. Although only two of eight patients who were negative for CEA mRNA suffered from peritoneal carcinomatosis, three more patients died of recurrences through other metastatic pathways. Multivariate analysis revealed that curability of the operation (knowledge of the CEA mRNA values excluded) and T categories were the only significant independent prognostic factors. CONCLUSIONS: RT-PCR of the peritoneal washes had little value as a prognostic factor, but identified over 80% of the patients planned for curative surgery to have disseminated cancer cells in the peritoneal cavity. Almost the same proportion of patients actually suffered from peritoneal carcinomatosis. These facts indicate why treatment with surgery alone rarely cures patients with linitis plastica.

Aged↗